Zimbra

Welcome to SendGrid’s Web API v3! This API is RESTful, fully featured, and easy to integrate with.

Email Validation Service. Use ZeroBounce's email validation API to increase your email marketing ROI! Remove invalid email addresses from your list using our unique email verification scrubbing system to prevent email bounces.

Easily check if a certain e-mail address is valid. Is it a valid domain? Is the e-mail a temporary/disposable e-mail? That's a common indicator of spamming/trolling, so now there's an API for you so you can easily block it!